Nick Grimshaw has lost 1.1 million listeners since he took the reins at Radio 1’s breakfast show from Chris Moyles. Photograph: Rex Features

The challenge for BBC Radio 1 just got tougher. The station formerly known as the "nation's favourite" is having to retune to a more youthful audience just as younger listeners are spending less time listening to radio.

The decline in the breakfast show's total listening hours was even more precipitous. Those who stayed listening tuned in for less time, an average of 2.6 hours a week, compared with the 3.5 hours they spent listening to Moyles. In all, total listening to the show fell 39%, from 23.6m hours to 14.5m hours a week. This reflects a decline in the amount of radio listening by young people across the board, from an average of 17.6 hours a week in 2009 to 15.4 hours a week. "They are significant numbers," say Radio 1's controller, Ben Cooper. "When you look across Europe you see that youth listening has reduced pretty much in all territories."

Radio 1's response, besides its new line-up and a playlist famously eschewing Robbie Williams, has been to turn to video in the hope it will end up saving, rather than killing, the radio star. The BBC's director general, Tony Hall, has also indicated he wants to see more collaboration between the station and its similarly youth-oriented TV sibling, BBC3, including the rebranding of BBC3's news as a TV extension of Newsbeat.

Cooper says: "The key for Radio 1 in making the BBC relevant for young people is to crack the smartphone generation, or as I call them, the head-down generation. That's the battle we are up against. There are so many things young people can do with their time now, and a lot of that is to do with the mobile phone. The most important thing facing radio today is not content or brands or anything like that. It's distribution."

Cooper will look to combat rival attractions such as YouTube and Spotify with the use of more video across Radio 1's output, including its own video channel on the BBC's iPlayer, and the launch of a new Playlister service that allows users to tag tracks they hear on BBC radio and play them on a streaming music service. Radio 1's iPlayer channel will include interviews by DJs, performances from its big live events and regular set-pieces from programmes such as the Radio 1 Live Lounge.

"You don't sit around the wireless listening with mother any more, you play with your mobile phone. It's about getting the great content we make day in, day out, onto that mobile phone," Cooper says. "We know there is a downward trend of listening hours. What we are trying to do is say OK, but we can make up for those lost hours of listening to the station with engagement in other ways. That's why our strategy is 'listen, watch and share'."

It will be no easy task. Adam Bowie, head of strategy and planning at Absolute Radio, says: "It's near-impossible for Radio 1 to lower its average age down to the levels the BBC Trust's service licence for Radio 1 would like. On the other hand, it's in everyone in the radio business's interest that Radio 1 does work hard to reach as young an audience as possible."

Radio 1 is vital if the BBC is to stay in touch with younger listeners. Evidence suggests that young people who do not listen to the radio do not suddenly switch on as they get older, and Hall made its importance clear when he appeared before MPs on the Commons culture, media and sport select committee last month.

"One of the areas I want to develop is how BBC3 and Radio 1 can work much more together, with Radio 1 concentrating much more on music and BBC3 on other genres," Hall said. "We have a news service on BBC3. We don't call it anything, yet we have Newsbeat on Radio 1. Why not take Newsbeat and run that across the two? The controllers of BBC3 [Zai Bennett] and Radio 1 have more work to do to see how together these two channels, stations, can [find] a younger audience."

The average age of Radio 1's adult audience remained stuck at 34 in the latest audience figures, falling to 32 if all listeners aged 10 and over are included. The good news for Cooper is that the modal age, the biggest single age group, listening to Radio 1 is now 18. Less encouraging was that just over 50% of its listeners are aged 30 or over. The challenge has only just begun.